U.S. patent number 11,033,184 [Application Number 16/575,825] was granted by the patent office on 2021-06-15 for self-illuminated handheld lens for retinal examination and photography and related method thereof.
This patent grant is currently assigned to University of Virginia Patent Foundation. The grantee listed for this patent is University of Virginia Patent Foundation. Invention is credited to Paul Andrew Yates.
United States Patent |
11,033,184 |
Yates |
June 15, 2021 |
Self-illuminated handheld lens for retinal examination and
photography and related method thereof
Abstract
System and method directed towards providing full and even
illumination of a patient's retina through lighting integrated into
a handheld fundus lens. By integrating the lighting, the method and
system reduces and even eliminate many lens artifacts and
reflections. By increasing the accuracy, quality, and field of view
afforded during clinical examination of the retina, the method and
system will allow practitioners to make more accurate diagnoses and
will increase safety during retinal surgical procedures.
Inventors: |
Yates; Paul Andrew
(Charlottesville, VA) |
Applicant: |
Name |
City |
State |
Country |
Type |
University of Virginia Patent Foundation |
Charlottesville |
VA |
US |
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Assignee: |
University of Virginia Patent
Foundation (Charlottesville, VA)
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Family
ID: |
43050473 |
Appl.
No.: |
16/575,825 |
Filed: |
September 19, 2019 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20200205652 A1 |
Jul 2, 2020 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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15869715 |
Jan 12, 2018 |
10426330 |
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14880621 |
May 8, 2018 |
9962071 |
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14268643 |
Feb 23, 2016 |
9265410 |
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13318695 |
Jun 3, 2014 |
8740383 |
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PCT/US2010/033875 |
May 6, 2010 |
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61175807 |
May 6, 2009 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04N
5/2256 (20130101); A61B 3/156 (20130101); A61B
3/1208 (20130101); A61B 3/125 (20130101); G06V
40/19 (20220101); A61B 3/12 (20130101); A61B
3/14 (20130101); H04N 5/2251 (20130101); A61B
3/0008 (20130101); H04N 5/2254 (20130101) |
Current International
Class: |
A61B
3/00 (20060101); G06K 9/00 (20060101); A61B
3/12 (20060101); A61B 3/125 (20060101); A61B
3/15 (20060101); A61B 3/14 (20060101); H04N
5/225 (20060101) |
Field of
Search: |
;351/219 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Hasan; Mohammed A
Attorney, Agent or Firm: Decker; Robert J.
Parent Case Text
RELATED APPLICATIONS
This application is a continuation application under 35 U.S.C.
.sctn. 120 of U.S. patent application Ser. No. 15/869,715, filed
Jan. 12, 2018, which is a is a continuation application under 35
U.S.C. .sctn. 120 of U.S. patent application Ser. No. 14/880,621,
filed Oct. 12, 2015, now U.S. Pat. No. 9,962,071, granted on May 8,
2018, which is a continuation application under 35 U.S.C. .sctn.
120 of U.S. patent application Ser. No. 14/268,643, filed May 2,
2014, now U.S. Pat. No. 9,265,410, granted on Feb. 23, 2016, which
is a division of U.S. patent application Ser. No. 13/318,695, filed
Nov. 3, 2011, now U.S. Pat. No. 8,740,383, granted on Jun. 3, 2014,
which is a national stage filing of International Application No.
PCT/US2010/033875, filed May 6, 2010, which claims the benefit of
priority under 35 U.S.C. .sctn. 119(e) of U.S. Provisional
Application Ser. No. 61/175,807, filed on May 6, 2009, entitled
"Self-Illuminated Handheld Lens for Retinal Examination and
Photography and Related Method thereof;" the disclosures of which
are hereby incorporated by reference herein in their entirety.
Claims
What is claimed is:
1. A self-illuminated handheld device for retinal examination of a
subject, said device comprising: a viewing lens; a contact lens to
be applied to an eye; an integrated light source; an annular light
channel through which light from the integrated light source is
transmitted to the eye; a light baffle separating the integrated
light source and the light channel from a central aperture between
the viewing lens and the contact lens; and wherein the device is
one of the following: smaller than 80 mm.times.100 mm.times.40 mm,
smaller than 100 mm{circumflex over ( )}3, smaller than 40
mm.times.50 mm.times.20 mm, or larger than 40 mm.times.50
mm.times.20 mm and smaller than 100 mm{circumflex over ( )}3.
2. The device of claim 1, wherein the annular light channel is
located behind, around, adjacent to or through the contact
lens.
3. The device of claim 1, wherein the annular light channel is a
thinning of the contact lens, a portion of the contact lens that
differs in power, a gap ground into or provided in the contact
lens, a gap around or adjacent to the contact lens, or a space
behind or adjacent to the contact lens.
4. The device of claim 1, further comprising: a diffusing insert
located in the light channel.
5. The device of claim 4, wherein the diffusing insert is a fiber
optic block.
6. The device of claim 4, wherein the diffusing insert is a
mini-optical diffuser.
7. The device of claim 1, further comprising: a power source in
communication with the integrated light source.
8. The device of claim 7, wherein the power source is integrated
into the device.
9. The device of claim 1, further comprising: an adjustable optical
mask.
10. The device of claim 9, wherein the adjustable optical mask is
mechanical, such as an embedded diaphragm.
11. The device of claim 9, wherein the adjustable optical mask is
electronic, such as a transparent liquid crystal display (LCD).
12. The device of claim 1, further comprising: a controller
providing for selective illumination of the eye.
13. The device of claim 12, wherein the controller is capable of
controlling at least one of the brightness, pattern, or timing of
the light from the integrated light source.
14. The device of claim 1, further comprising: a plurality of fiber
optic cables transmitting light from the integrated light source
and providing a ring of illumination through the annular light
channel.
15. The device of claim 14, wherein the annular light channel is
located behind, around, adjacent to or through the contact
lens.
16. The device of claim 14, wherein the annular light channel is a
thinning of the contact lens, a portion of the contact lens that
differs in power, a gap ground into or provided in the contact
lens, a gap around or adjacent to the contact lens, or a space or
adjacent to behind the contact lens.
17. An illumination system configured to control temporal and
spatial illumination of a wide field of view of the retina of an
eye of a subject comprising: a viewing lens configured to visualize
said wide field of view of said retina of said eye; an integrated
light source comprising at least one of individual LEDs; wherein
configuration of said individual LEDs are such that each of said
individual LEDs illuminate a partial area of said wide field of
view of said retina; a microcontroller configured to control the
pattern and intensity of one or more of said individual LEDs; and a
microprocessor configured to provide instructions to said
microcontroller to control the pattern and intensity of one or more
of said individual LEDs such that said individual LEDs provide
partial illumination of said wide field of view of said retina.
18. The system of claim 17, further comprising: an image recording
device; a lens-to-camera interface configured to transmit an image
from said viewing lens to said image recording device; said
instructions are configured to control the pattern and intensity of
one or more of said individual LEDs such that said LEDs provide
partial illumination of said wide field of view of said retina in a
serial manner; and said image recording device is configured to
record at least one said image when said microcontroller controls
said individual LEDs to illuminate said partial area of said wide
field of view.
Description
FIELD OF THE INVENTION
The present invention is directed to an improved device for retinal
examination and related methods. More specifically, aspects of the
present invention are directed to handheld fundus lenses with
integrated lighting that are self-contained.
BACKGROUND OF THE INVENTION
Clinical examination and treatment of retinal disease has not
fundamentally changed in the last 100 years, relying on a slit lamp
biomicroscope which consists of a binocular stereo microscope, a
handheld condensing lens, and a slit lamp providing illumination to
examine the retina, as seen in FIG. 1A. A slit beam of light is
created by the slit lamp and shone through a handheld lens placed
in front of the patient's eye. The handheld lens produces an image
that is visualized through the oculars of the biomicroscope.
Unfortunately, this technique suffers from significant image
aberrations induced by light reflections off the handheld lens,
which limits the practical view to only a thin slice of retina
comprising less than 1% of the total retina surface area. FIG. 1B
is a typical image of the retina provided by slit beam illumination
and a handheld lens. Note the limited field of view and significant
lens reflections present. The position of the slit must be
maneuvered to examine different parts of the retina. Image quality
even from this slit is often significantly degraded, making retinal
diagnosis difficult. In contrast, conventional retinal photography
routinely is capable of 50 degree aberration and reflection free
fields of view of the retina. FIG. 1C is a standard fundus camera
image of a retina. There is significantly greater retinal detail
and a much wider field of view compared to the slit lamp image of
FIG. 1B. No lens reflections or image aberrations are present,
greatly facilitating diagnosis of retinal diseases. Unfortunately,
these photographic advances have yet to be translated in any
meaningful way into improvements in the clinical exam.
There are currently 16 million diabetic patients in the United
States who require yearly, dilated retina exams as part of their
recommended eye care. Half of these patients will have some form of
retinopathy present at the time of exam. For the majority of these
patients, slit lamp retinal examination is the only modality used
to document their retinal findings. Retina photos are used as an
adjunct to the clinical exam in only 10-20% of patients, as this
involves separate time consuming procedures by the ophthalmic
photographer. This makes it imperative that a clear and reliable
view of the retina is available to the clinician for accurate
diagnosis.
Ten percent of diabetic patients will eventually develop
proliferative diabetic retinopathy, requiring panretinal laser
photocoagulation (PRP) to ablate their peripheral retina in an
attempt to preserve central foveal vision. FIG. 2A illustrates a
retina after PRP. Laser photocoagulation may be delivered via slit
lamp techniques using widefield (>75 degree field of view)
handheld lenses. These lenses, relying on the same slit
illumination, suffer significantly greater reflection artifacts
than the narrow field (<75 degree field of view) handheld lenses
used for clinical exam of the macula. FIG. 2B illustrates a
clinician's view at a slit lamp while performing PRP. A handheld
contact lens is applied to a patient's eye and slit lamp
illumination is used to visualize the retina and the aiming beam
for the laser. Retinal detail is severely compromised from lens
reflections and the limited field of view afforded by the slit
illumination. The risk of inadvertent laser to the fovea is
significant due to the obscuration of the optic nerve by this
pattern of poor illumination and lens reflections. The slit beam
must be constantly moved to reorient to the location of the optic
nerve to verify retinal position and avoid inadvertent ablation of
the central vision with laser. The limited and generally poor
illumination provided by the slit beam substantially increases the
time required for laser treatment and poses a significant and
unnecessary safety hazard due to poor identification of retinal
location.
Many diabetic patients with proliferative diabetic retinopathy
proceed to develop chronic vitreous hemorrhages and decreased
vision, requiring surgical removal of the blood in some cases. Poor
illumination also poses a safety hazard for their retinal surgery.
Standard pars plana vitrectomy technique relies on fiber optic
illumination provided by a rigid 20 or 23 gauge probe inserted
through the pars plana of the eye. Limited beam divergence of the
fiber optic probe provides spot illumination of the retina, with
details of the surrounding peripheral retina remaining poorly
illuminated, as seen in FIG. 2C. This leads to an increased
likelihood of instrument error causing permanent retinal damage.
Greater surgical safety and decreased surgical times would be
facilitated by a widefield general illumination of the retina in
addition to the spot illumination provided by the fiber optic
probe.
Commercial developments in ophthalmic photography over the last 40
years have clearly demonstrated that the retina can be imaged at
high resolution and that image distortions/reflections can be fully
corrected to enable accurate diagnosis of retinal disease. The
hallmark of the difference in retinal photography over clinical
exams is the different pattern of illumination used in each, as
illustrated in FIG. 3A. Contemporary retina cameras generate a ring
or "donut" of illumination centered on the pupil. This circular
illumination provides an even/full illumination of the retina with
minimal lens reflections. Imaging rays reflected from the back of
the retina are collected from the middle of the "donut," which
substantially decreases lens reflections. Most commercial retina
cameras are able to obtain a 50 degree field of view of the retina
with this technique FIG. 1C, but are not able to achieve widefield
(>75 degrees field of view) images such as shown in FIG. 2A.
Narrowfield cameras are non-contact, with the camera never touching
the front surface of the eye. In contrast, widefield cameras often
require direct contact of the imaging system with the cornea. The
commercial RETCAM II retinal camera is an example of a widefield
camera which directly contacts the cornea. This camera creates a
donut of light using a solid fiber optic ring to couple an external
illumination light directly to the cornea, as shown in FIG. 3E.
FIG. 3C shows a sample image from the Retcam II. This illumination
design, while a significant improvement on slit lamp illumination,
still suffers from significant corneal haze, as well as unevenness
in central illumination, as compared to peripheral illumination,
due to issues with the illumination design. Further, the RETCAM II
is designed for retinal photography and as specified is not capable
of use in handheld clinical examination through a slit lamp
biomicroscope. The device has electrical power and fiber optic
light coupled into a sizable imaging wand that is significantly
larger than existing handheld fundus lenses, severely limiting the
unit's portability and ease of use. The design of the illuminating
ring requires intricate manufacturing that would not be amenable to
inexpensive handheld lenses. All these issues are addressed in
various embodiments of the present invention, which is a
significant improvement over contemporary designs.
An improved method of illumination is needed to provide a wider
field of view of the retina and to eliminate those lens reflections
that result from external slit illumination of the handheld
condensing lens. The ideal illumination for the retina is a ring of
light focused on the eye with a diameter slightly less than the
pupil diameter. Prior designs (Pomerantzeff et al., U.S. Pat. No.
3,944,341, and Massie et al., U.S. Pat. No. 5,822,036, of which are
incorporated by reference herein in their entirety) have adapted a
method of illumination into designs for retinal photography, as
opposed to clinical examination. These two designs rely on an
external illumination device that is then routed by means of fiber
optic coupling into a contact lens that is used to view the
retina.
These existing devices, while may be an improvement over
non-illuminated handheld lenses, suffer from a number of design
constraints that do not allow them to be used for handheld fundus
examination at the ophthalmic slit lamp. Pomerantzeff relies on two
rows of individual fiber optic elements that are cemented into a
contact lens with the fiber optics directly contacting the cornea.
This presents issues with sterilization due to the inevitable
breakdown of the cementing compound and lodging of bacteria into
the cemented area surrounding it. It also requires technically
difficult fiber optic polishing so that the individual fibers do
not damage the cornea and are all at the same plane. By focusing
the ring of light on the cornea through means of fiber optics,
significant corneal haze is generated which lowers overall image
contrast. There is a complicated five stage optical element design
to produce an image which leads to an unnecessarily bulky lens that
could not be easily manufactured or handheld due to its overall
size. The directionality of the fiber optics, while illuminating
some of the peripheral retina, do not illuminate the central
portion of the retina well, leaving the macula less exposed to
light compared to the peripheral retina. A separate illuminator is
required that is external to the device, requires electrical power,
and limits portability of this device. The device is intended for
retinal photography and is not optimized or usable for slit lamp
examination. The focus of the five lens design is intended to focus
reflected retina light on an imaging device directly attached to
the lens, rather than at the distances required by ophthalmic slit
lamp examination. Finally, the patent has not resulted in a
commercial device in the 30 years since it was originally
issued.
The patent by Massie et al. has similar limitations to the earlier
design of Pomerantzeff. Fiber optic illumination is used to direct
the light from an external illumination source into the imaging
lens, reducing portability of the unit. The device is intended only
for retinal photography with an imaging device built into the
handheld unit and then electrically connected to a larger external
imaging control unit. There is no clear optical axis that would
allow use of the device at the ophthalmic slit lamp. The design is
intended to focus the light from the retina onto an imaging device
that is located directly behind the contact lens rather than at the
distances required by handheld condensing lenses used at an
ophthalmic slit lamp. The use of fiber optics for coupling of an
external illumination source limits the diffusion of the
illuminating light beam and provides only partial illumination of
the retina with a dark central retina, as also seen with the
Pomerantzeff design. While the Massie design allows for
illumination by placing a second central illumination source
contained within the handheld unit itself to illuminate central
retina, it obscures the central axis of the lens, which eliminates
visualization of the retina through the center of the lens; a
function essential to a handheld condensing lens. The design
additionally attempts to improve the illumination produced by fiber
optic through use of up to three additional lens elements at the
end of the fiber optic, which again complicates construction and
alignment of this device. Similar to the Pomerantzeff design,
Massie's coupling of light fiber optically directly to the corneal
surface results in significant corneal haze which degrades image
contrast.
Fine polishing of the fiber optic is required to angle the exit of
the light to improve the area of the retina illuminated. However,
the angle cut required on the fiber optic reduces transmission of
the light due to the oblique exit of the light from the fiber optic
element. Finally, the design of the Massie device results in a
bulky imaging unit that far exceeds the typical 40 mm depth of a
handheld fundus lens. All of these design issues that are optimized
for retinal photography limit the ability of this design to be used
as a self illuminated handheld condensing lens for retinal
examination.
Next, Miller et al., U.S. Pat. No. 7,048,379, discloses an imaging
lens and illumination system for a retinal camera. Miller's ring
illumination was focused on the patient's retina through a front
objective lens. The lighting is located behind the objective lens,
and the camera is not designed with a contact lens.
Contemporary retinal photography designs are capable of attaining
better quality images and a wider field of view with less
reflections than conventional slit lamp illumination. However, they
remain limited by size, portability, poor illumination, and poor
image contrast. Massie and Pomerantzeff produced devices which have
no direct view through the lens that is available for the
practitioner to directly visualize the retina (as both are intended
for retinal photography) and are too large to be of practical use
in clinical examination. Further, their complicated designs render
them expensive to manufacture. Finally, they still suffer from
problems with full and even illumination.
Providing the versatility and speed of clinical examination with
the accuracy and clarity of retinal photography would provide
greatly improved image quality, permitting significantly wider
fields of view, better resolution of retinal detail for diagnosis,
and safer surgical intervention to treat retinal disease.
SUMMARY OF THE INVENTION
An aspect of an embodiment of the present invention seeks to
correct the illumination issues with current handheld fundus
lenses. The slit lamp biomicroscope may be used to view the image
through the handheld retina lens, but the handheld lens itself
would provide the illumination of the retina, rather than relying
on slit illumination provided by the slit lamp. An aspect of
various embodiments of the present invention captures the
illumination characteristics of retinal camera design in miniature,
creating a design that may be battery powered and simple to
manufacture, maintaining commercial viability. An embodiment
provides, among other things, a handheld lens where ring
illumination is directly coupled to the contact lens portion of the
handheld lens, as illustrated in FIG. 3B. This creates a ring or
"donut" of illumination that is transmitted to the eye when the
front contact lens of the device is applied to the cornea. This
ring could be created through many designs, including a ring of
surface mount LEDs, the use of fiber optics to fashion donut
illumination from a point source of light, the use of a shaped
mirror to provide a dispersed donut of light, and a curved surface
with surface mount LEDs providing multidirectional illumination.
FIG. 3D illustrates the potential viewing area of such a widefield
handheld contact imaging lens of FIG. 3B.
An aspect of an embodiment of the present invention provides a
self-illuminated handheld lens (and related method) to aid in the
examination and treatment of retinal disease. Retinal exams and
retinal laser treatments are commonly performed using a slit lamp
biomicroscope. The slit lamp uses a narrow beam of light that
illuminates less than 1% of the total retinal surface and suffers
from significant optical aberrations that obscure retinal details.
To alleviate these problems, an embodiment of the present invention
provides a self-illuminated handheld fundus lens for retinal
imaging to be used in conjunction with the slit lamp biomicroscope
to provide clear, reflection free, wide field illumination and view
of the retina. An aspect of an embodiment of the present invention
device creates ring illumination that is coupled through the
contact lens of a handheld fundus lens to provide this widefield
illumination of the retina. An embodiment of the present invention
device may rely on use of fiber optics and/or light emitting diodes
to provide illumination, though many other means of illumination
are possible.
An aspect of an embodiment of the present invention provides a
self-illuminated handheld device for retinal examination of a
subject. The device may comprise: a viewing lens; a contact lens to
be applied to an eye; an integrated light source; an annular light
channel through which light from the integrated light source is
transmitted to the eye; and a light baffle separating the
integrated light source and the light channel from a central
aperture between the viewing lens and the contact lens.
An aspect of an embodiment of the present invention provides a
system and related method for retinal photography. The system
includes a self-illuminated handheld fundus lens, whereby the
self-illuminated fundus lens may comprise: a viewing lens; a
contact lens to be applied to an eye of a subject; an integrated
light source; an annular light channel through which light from the
integrated light source is transmitted to the eye; and a light
baffle separating the integrated light source and the light channel
from a central aperture between the viewing lens and the contact
lens. Moreover, the system may also include: an image recording
device; and a lens-to-camera interface, adapted to transmit an
image from the lens to the image recording device.
An aspect of an embodiment of the present invention provides a
self-illuminated handheld device (and related method) for retinal
examination of a subject. The device may comprise: a viewing lens;
a contact lens to be applied to an eye; an integrated light source;
an annular light channel through which light from the integrated
light source is transmitted to the eye, the annular light channel
is a thinning of the contact lens, a portion of the contact lens
that differs in power, a gap ground into or provided in the contact
lens, a gap around or adjacent to the contact lens, or a space
behind or adjacent to the contact lens and is located behind,
around, adjacent to or through the contact lens; a light baffle
separating the integrated light source and the light channel from a
central aperture between the viewing lens and the contact lens; and
an integrated power source in communication with the integrated
light source.
An aspect of an embodiment provides a self-illuminated handheld
lens for wide angle retinal viewing of a subject eye, comprising:
an aspherical viewing lens having a symmetric viewing axis and
defining a central aperture; plurality of LEDs positioned around
the viewing axis and configured to emit light to illuminate the
subject eye; an electronic controller powering the plurality of
LEDs and controlling each individual LED or a series of LEDs
independently; and a light baffle configured to block stray light
of the plurality of LEDs from getting into the central aperture. An
aspect of an embodiment of the present invention provides a method
(and related system) for illuminating the cornea/retina of an eye
of a subject through a handheld device. The method may comprise:
generating light from one or more light sources; reflecting the
light off a mirrored surface; transmitting the light through an
annular light channel proximal to a contact lens; and receiving an
illuminated image from the eye through a viewing lens.
An aspect of an embodiment of the present invention provides an
illumination system configured to control temporal and spatial
illumination of a wide field of view of the retina of an eye of a
subject. The system may comprise: a viewing lens configured to
visualize said wide field of view of said retina of said eye; an
integrated light source comprising at least one of individual LEDs;
wherein configuration of said individual LEDs are such that each of
said individual LEDs illuminate a partial area of said wide field
of view of said retina; a microcontroller configured to control the
pattern and intensity of one or more of said individual LEDs; and a
microprocessor configured to provide instructions to said
microcontroller to control the pattern and intensity of one or more
of said individual LEDs such that said individual LEDs provide
partial illumination of said wide field of view of said retina.
Moreover, in an embodiment the system may further comprise: an
image recording device; a lens-to-camera interface configured to
transmit an image from said viewing lens to said image recording
device; said instructions are configured to control the pattern and
intensity of one or more of said individual LEDs such that said
LEDs provide partial illumination of said wide field of view of
said retina in a serial manner; and said image recording device is
configured to record at least one said image when said
microcontroller controls said individual LEDs to illuminate said
partial area of said wide field of view.
These and other objects, along with advantages and features of
various aspects of embodiments of the invention disclosed herein,
will be made more apparent from the description, drawings and
claims that follow.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated into and form a
part of the instant specification, illustrate several aspects and
embodiments of the present invention and, together with the
description herein, serve to explain the principles of the
invention. The drawings are provided only for the purpose of
illustrating select embodiments of the invention and are not to be
construed as limiting the invention.
FIG. 1A schematically illustrates a slit lamp biomicroscope.
FIG. 1B demonstrates a typical image provided by a slit lamp
biomicroscope with use of a contemporary handheld lens and standard
slit lamp illumination.
FIG. 1C demonstrates a typical image provided by a fundus camera,
with the same scale as used in FIG. 1B.
FIG. 2A illustrates a retina after undergoing panretinal
photocoagulation (PRP) for treatment of proliferative diabetic
retinopathy.
FIG. 2B illustrates a clinician's view at a slit lamp biomicroscope
during performance of PRP using a contemporary widefield handheld
lens with standard slit lamp illumination.
FIG. 2C illustrates a retina surgeons's view through an operating
microscope during pars plana vitrectomy surgery.
FIG. 3A illustrates the typical "donut" illumination used by most
commercial retina cameras.
FIG. 3B schematically illustrates an embodiment of the present
invention handheld fundus lens that provides its own ring
illumination built into its contact lens.
FIG. 3C demonstrates a sample image and design of a commercial
retina camera.
FIG. 3D illustrates the field of view obtained by the widefield
lens of FIG. 3B, which can visualize the full 165 degrees field of
view of the retina.
FIG. 3E schematically illustrates the commercial retinal camera,
RETCAM II.
FIG. 3E shows the commercial retinal camera, RETCAM II.
FIG. 4 schematically illustrates an embodiment of the present
invention, utilizing fiber optic cables to couple light from either
an external light source, or a light source built into the handheld
lens itself to illuminate the retina.
FIG. 5 schematically illustrates an embodiment of the present
invention, utilizing light emitting diodes to illuminate the
retina.
FIG. 6 schematically illustrates an embodiment of the present
invention, utilizing a combination of fiber optic cables and a
mirrored surface to illuminate the retina.
FIG. 7 schematically illustrates an embodiment of the present
invention, utilizing a combination of light emitting diodes and a
mirrored surface to illuminate the retina.
FIGS. 8A-8B schematically illustrate a possible configuration of
components in an assembled view and exploded view, respectively,
that can be used to implement, for example, but not limited
thereto, the embodiment shown in FIG. 7, which utilizes a
combination of light emitting diodes and a mirrored surface to
illuminate the retina.
FIG. 9 schematically illustrates one embodiment of the present
invention, utilizing a combination of xenon flash lighting and a
mirrored surface to illuminate the retina.
FIG. 10 schematically illustrates one embodiment of the present
invention, utilizing light emitting diodes mounted on a curved
surface to illuminate the retina.
FIGS. 11A-11B schematically illustrate the external casing of an
embodiment of the present invention in side ways position and
upward position, respectively.
FIGS. 12A-12B schematically illustrate the use of an embodiment of
the present invention as part of a system for retinal
photography.
FIG. 13A shows a view of a model eye using, for example, the
embodiment of FIG. 10.
FIG. 13B shows a view of a model eye using, for example, the
embodiment of FIG. 10.
FIG. 13C shows an image taken by a contemporary retinal camera. The
image is obscured by corneal haze.
DETAILED DESCRIPTION OF THE INVENTION
Aspects of the present invention are directed towards providing
full and even illumination of a patient's retina through lighting
integrated into a handheld fundus lens. By integrating the
lighting, aspects of the present invention reduce and even
eliminate many lens artifacts and reflections. By increasing the
accuracy, quality, and field of view afforded during clinical
examination of the retina, an aspect of the present invention will
allow practitioners to make more accurate diagnoses and will
increase safety during retinal surgical procedures.
An aspect of an embodiment of the current invention is designed to
provide, among other things, self-contained ring illumination of
the retina within the space constraints of a handheld fundus lens
which measures approximately 40 mm.times.50 mm.times.20 mm, and
optimized for visualization of retinal details by a trained
practitioner at an ophthalmic slit lamp. As portability of the unit
may be advantageous to marketability and acceptance of this device,
the design may be focused on this design constraint for the various
embodiments of this invention. While this specific size is the
average size of a handheld lens, it will be readily understood that
larger lenses may still meet the handheld design constraint. We
also consider other embodiments that meet some but not all of these
design constraints, as they may be preferred under certain
circumstances. It should be appreciated that the devices and
systems of the various embodiments discussed throughout this
disclosure may be implemented to be larger or smaller than the
dimensions of 40 mm.times.50 mm.times.20 mm, as desired or
required.
Several embodiments of the present invention are discussed below.
However, the invention may be embodied in other forms without
departing from the spirit or essential characteristics of the
present invention. It is therefore to be understood that the
following embodiments are to be considered illustrative rather than
limiting of the invention described herein.
An embodiment of the present invention provides a handheld lens 11
for illuminating a patient's retina 101 from a point source of
light through fiber optics cables. This embodiment is illustrated
in FIG. 4. In this embodiment, there is a light source 1 outside of
the lens that is directly coupled to fiber optic cable 2. Light
source 1 may be any bright light. In one embodiment it would
consist of a white, infrared, or color high intensity LED light
source as these light sources have low power requirements amenable
to battery power. In another embodiment it would include halogen or
xenon flash lighting which may or may not require electrical line
power to achieve higher intensity illumination than could be
provided by LEDs. The fiber optic cable 2 may be composed of
multiple thin fiberoptic strands. These individual strands are
reformed into a ring illumination that directly abuts the contact
lens 3. A light channel 4 is ground into the contact lens 3 and
fiber optic cable 2 inserts into this light channel 4. The light
channel 4 may be around, through, adjacent or behind contact lens
3. It is through the light channel 4 that light from the fiber
optic cable 2 is transmitted to the retina 101. The light channel 4
may be a thinning of the contact lens 3, a portion of the contact
lens 3 that differs in power, a gap ground into or provided in the
contact lens 3, a gap around or adjacent to the contact lens 3, or
a space behind or adjacent to the contact lens 3. The fiber optic
cable 2 is located in a separate light cavity 5 of the handheld
lens 11 with a light baffle 6 to prevent stray light from entering
the central aperture 12 of the lens cavity 15 and the viewing field
of a viewing lens 7. The sides of the light channel 4 are covered
with material to prevent transmission of stray light from the light
channel 4 into contact lens 3 which would obscure the image viewed
through the viewing lens 7. Light from the light source 1,
transmitted through the fiber optic cable 2 and light channel 4 to
the retina 101, reflects back through the contact lens 3 and
viewing lens 7 resulting in an image 100.
Contemporary designs utilized an angle cut and polished solid
one-piece fiber optic insert to transmit light to the contact lens.
As has been noted, this has the disadvantage of decreasing
transmission of light from the end of the fiberoptic due to the
oblique angle of the cut end. Further, light emerging from the end
of the fiberoptic does not provide a diffuse light source as is
required to illuminate the entire retina. One aspect of the current
invention solves this limitation through a diffusing insert. Two
exemplary implementations are now described. In the first, the
individual fiber optic strands of fiber optic cable 2 enter a fiber
optic block 8 perpendicular to its surface. The fiber optic block 8
is optionally inserted into the light channel 4. Each strand of the
fiber optic cable 2 is threaded into a hole in the fiber optic
block 8. The hole for each strand of the fiber optic cable 2 is
progressively angled so that the directionality of light from the
individual strands as they emerge at the distal end of the fiber
optic block 8 is different. This allows illumination to be directed
from individual fibers both centrally and peripherally so that no
difference in illumination occurs as was found in contemporary
designs. A second exemplary approach is to optionally embed a
mini-optical diffuser 9 within the light channel 4, replacing the
fiber optic block 8. A Mini-optical diffuser 9 scatters the
incident light from the incoming strands of the fiber optic cable
2, thereby reducing the strong directionality of the fiberoptic
light. This provides more even illumination with
multidirectionality of light to provide even illumination of both
peripheral and central retina than contemporary designs. This is
also a technically more efficient and pragmatic design than the
multiple added lens elements used in contemporary designs to reduce
the directionality of the light.
In order to obtain selective illumination of the retina 101, an
adjustable optical mask 16 may be used. This mask may be physical,
such as an adjustable diaphragm, or electronic, such as a
transparent liquid crystal display. Use of the adjustable optical
mask 16 would allow a clinician to control which portion of the
retina 101 is illuminated.
Another embodiment of the present invention provides a handheld
lens 11 utilizing a ring of light-emitting diodes (LEDs) to provide
illumination to the retina 101 and is illustrated in FIG. 5. The
illustrated embodiment provides ring illumination directly within
handheld lens 11 using a ring of LEDs 10. LEDs 10 may be high
intensity white, infrared, or colored. Utilizing different types of
LEDs allows for imaging of either red free, infrared, or
fluorescent dyes which are commonly used to evaluate retinal
function. In one implementation of this embodiment, an optical
diffuser 13 is used to reduce the point source characteristics of
the LEDs 10. The light from the LEDs 10 remains contained within
the light cavity 5 and light baffle 6 so that stray light does not
enter the central aperture 12 of the lens cavity 15 or the viewing
area of the viewing lens 7. The light enters the light channel 4
and is transmitted to the retina 101. As the sides of light channel
4 are coated to block light from entering contact lens 3, an
effective optical circular ring mask is created. Light is only
transmitted from the distal end of the light channel 4, directly
adjacent to the patient's cornea. It is through the light channel 4
that light from LEDs 10 is transmitted to the retina 101. The light
channel 4 may be a thinning of the contact lens 3, a portion of the
contact lens 3 that differs in power, a gap ground into or provided
in the contact lens 3, a gap around or adjacent to the contact lens
3, or a space behind or adjacent to the contact lens 3. Light from
the LEDs 10, transmitted through the light channel 4 to the retina
101, reflects back through the contact lens 3 and viewing lens 7
resulting in an image 100.
In cases where central or mid peripheral retinal illumination is
required, this will provide sufficient even illumination of the
retina. In instances where a wider field of illumination is needed,
a mini-optical diffuser 9 at the distal end of the light channel 4
is used to scatter the illumination evenly across the entire
retina. An alternative embodiment is to place a fiber optic ring
block 8 into the light channel 4. Small lengths of fiber optic
strands 12 run throughout the fiber optic block 8. As in the
preceding embodiment, the small lengths of fiber optic strands 12
may be angled to redirect the light at all incident angles to
provide full and even illumination of central and peripheral
retina.
In some contemporary designs, two rings of fiberoptic illumination
were embedded into the contact lens to adjust for different pupil
sizes. Either one or the other ring would be illuminated to provide
the optimal retinal illumination. One aspect of the present
invention proposes to address this by placing an adjustable optical
mask 16 within light channel 4. The size of the adjustable optical
mask 16, limiting the amount and shape of the light passing through
the contact lens 3, may be controlled by the practitioner according
to required pupil size. This may be done either mechanically
through manual adjustment of an embedded diaphragm or in an
alternative embodiment an electronic transparent LCD is embedded
into the light channel 4 and individual pixels are controlled
electronically to set the size of the ring mask. Thus, the device
can be used on multiple patients and the size of the ring
illumination customized to their particular pupil size to provide
optimal retinal illumination.
In order to obtain selective illumination of the retina 101 by the
LEDs 10, a controller 17, such as a microcontroller, may be used.
This controller 17 allows for control of which LEDs of LEDs 10 are
illuminated, for how long (e.g., various temporal characteristics),
and how bright. Use of controller 17 would allow a clinician to
control which portion of the retina 101 is illuminated (e.g.,
pattern or spatial arrangement).
It should be appreciated that a controller and/or processor may be
in communication with any of the components or systems disclosed
herein, as desired or required.
Another embodiment of the present invention provides a handheld
lens 11, which involves the use of an annular mirror to scatter
light from a light source and transmit it to a patient's eye. One
such embodiment is illustrated in FIG. 6. In this embodiment, the
shape of the mirror is designed to create even illumination of both
central and peripheral retina. The fiber optic cable 2 is used to
transmit light from the light source 1 through the light cavity 5.
The light source 1 may be any bright light. In an embodiment it may
consist of a white, infrared, or color high intensity LED light
source as these light sources have low power requirements amenable
to battery power. In another embodiment it would include halogen or
xenon flash lighting, which may or may not require electrical line
power to achieve higher intensity illumination than could be
provided by LEDs. The fiber optic cable 2 may be composed of
multiple thin fiberoptic strands. The light from the fiber optic
cable 2 is then reflected off of the mirrored surface 21 through
the light channel 4 and contact lens 3, into the patient's eye. It
is through the light channel 4 that light from the LEDs 10 is
transmitted to the retina 101. The light channel 4 may be a
thinning of the contact lens 3, a portion of contact lens 3 that
differs in power, a gap ground into or provided in the contact lens
3, a gap around or adjacent the contact lens 3, or a space behind
or adjacent to the contact lens 3. In one embodiment, the mirrored
surface 21 is designed to provide even illumination of the retina
by reducing the directionality of the light. The mirrored surface
21 also prevents light from entering the central aperture 12 of the
lens cavity 15 and the viewing area of the viewing lens 7. In this
sense, the mirrored surface 21 serves a similar purpose to the
light baffle 6. The focus point for the scattered light reflected
from the mirrored surface is not at the corneal surface as occurs
with contemporary fiber optic designs. This feature significantly
reduces corneal haze that is present in contemporary designs. Light
from the light source 1, transmitted through the fiber optic cable
2, off of the mirrored surface 21, and through the light channel 4
to the retina 101, reflects back through the contact lens 3 and the
viewing lens 7 resulting in an image 100.
A similar embodiment is illustrated in FIG. 7. This embodiment
provides a handheld lens 11 which utilizes a ring of the surface
mounted LEDs 10 and a mirrored surface 21 to illuminate a patient's
retina 101, providing a ring of light. Light from the LEDs 10 is
emitted in the light cavity 5. The LEDs 10 may be high-intensity
white, infrared, or colored. The light is reflected off of the
mirrored surface 21 through the light channel 4 and contact lens 3,
into the patient's eye. In an embodiment, the mirrored surface 21
is designed to provide even illumination of the retina by reducing
the directionality of the light. In other embodiments, the mirrored
surface can be shaped to provide a different pattern of retinal
illumination needed for a particular use. The mirrored surface 21
also prevents light from entering the central aperture 12 of the
lens cavity 15 and the viewing area of the viewing lens 7. In this
sense, mirrored surface 21 serves a purpose similar to the light
baffle 6. Light from the LEDs 10, transmitted off of the mirrored
surface 21 and through light channel 4 to the retina 101, reflects
back through the contact lens 3 and viewing lens 7 resulting in an
image 100.
An embodiment of the present invention allows a practitioner
control over the illumination pattern by direct control of
individual LEDs 10. A controller 17 is connected to each individual
LED or a series of LEDs to allow a practitioner spatial, temporal,
and intensity control over the LEDs 10. A practitioner can choose
which LED lights are on and their radiance. By illumination of only
a few LEDs in the ring of LEDs, this allows for selective sectoral
illumination of the retina 101. Illumination can be focused on
peripheral versus central retina, allowing a practitioner to focus
on one area of the retina. This maintains an advantage over
contemporary slit lamp illumination in that larger areas of the
retina can be illuminated at one time that afforded by the slit
beam. The image 100 also has significantly reduced reflections and
enhanced image contrast compared to contemporary designs. This
sectoral illumination capability is advantageous for reduction of
the embodiment to practice. Patient tolerance to illumination
varies significantly, and control of individual LED brightness
allows an illumination pattern to be set that is both comfortable
for the patient and allows evaluation and treatment of specific
areas of the retina. This particular embodiment envisions use of a
controller 17 with the LEDs 10 to allow for sectoral illumination.
However, the particular embodiment used to control illumination
levels and allow sectoral illumination may comprise other methods,
including but not limited to a diaphragm, LCD mask, or neutral
density filter. There is no capability for this specific control of
the illumination pattern in contemporary designs, which limits
their practical use in some patients.
In an embodiment, the controller 17 can be triggered by a camera
flash to allow all of the LEDS 10 to turn on momentarily at high
brightness for the purposes of retinal photography. In an
embodiment, the controller 17 can be used to control the intensity
of infrared LEDs to allow focusing of the image from the handheld
lens and then control interspaced white LEDS, turning them on
momentarily at high brightness for the purposes of retinal
photography
FIGS. 8A-B illustrate a configuration of components in an assembled
view and exploded view, respectively, to implement the handheld
lens embodiment, for example, but not limited thereto, as described
in FIG. 7. A LED mounting 32 surrounds the mirrored surface 21 and
the LEDs 10 are mounted on the interior surface of the LED mounting
32. The contact lens 3, LED housing 32, mirrored surface 21, and
viewing lens 7 each fit within a LED housing 31 and casing 33. The
configuration allows the objective viewing lens 7 and casing 33 of
the handheld lens to be separated from the integrated illumination
contained in LED housing 31. If a configuration for illumination is
needed for a particular application of retinal imaging, one
particular LED housing 31 providing one configuration of
illumination can be replaced with another LED housing 31 providing
another configuration of illumination. The LED housing 31 can also
be changed depending on the size of the patient's eye, exemplified
by use of the handheld lens on neonatal versus adult patients. The
interchangeability eliminates the need for separate lenses for
different patient populations.
FIG. 9 illustrates an embodiment providing for the use of xenon
flash lighting 91 in place of LEDs 10. The xenon flash lighting 91
emits light which is reflected off of the mirrored surface 21 and
transmitted to the patient's eye. Use of xenon flash lighting 91
provides for a higher intensity light than achieved by LED or fiber
optic illumination and eliminates the need to fiber optically
couple flash illumination to the handheld lens. In an embodiment
xenon flash lighting 91 would be used for retinal photography.
An embodiment of the present invention, illustrated in FIG. 10,
provides for a handheld lens 11 utilizing surface-mounted LEDs 41
on a curved surface 42 to illuminate a patient's retina 101. The
surface-mounted LEDs 41 may be high-intensity white, infrared, or
colored. Surface-mounted LEDs 41 may be positioned on curved
surface 42 so as to provide even illumination across the patient's
retina. Light from the surface-mounted LEDs 41 enters the light
cavity 5 and is transmitted to the patient's eye through the light
channel 4 and contact lens 3. It is through the light channel 4
that light from the surface-mounted LEDs 41 is transmitted to the
retina 101. The light channel 4 may be a thinning of the contact
lens 3, a portion of the contact lens 3 that differs in power, a
gap ground into or provided in the contact lens 3, a gap around or
adjacent the contact lens 3, or a space behind or adjacent to the
contact lens 3. The light is multidirectional in nature due to the
shape of the curved surface 42. The curved surface 42 can be shaped
to provide any pattern of illumination needed for a particular
application of the handheld lens. The curved surface 42 also serves
to prevent the light from entering the central aperture 12 of the
lens cavity 15 and the viewing area of the viewing lens 7. Light
from the surface-mounted LEDs 41, transmitted through the light
channel 4 to the retina 101, reflects back through the contact lens
3 and viewing lens 7 resulting in the image 100.
The embodiment of FIG. 10 provides a matrix of the surface-mounted
LEDs 41 to allow an exquisite degree of temporal and spatial
control of retinal illumination not available in contemporary
designs. This embodiment may be may be advantageous in using the
invention in some patient populations depending on application or
patient constraints. In particular, placement of the
surface-mounted LEDs 41 directly on the curved surface 42 allows
for a smaller LED housing 31 than in other embodiments, which may
be needed for certain patient populations such as neonates, or for
particular applications such a vitreoretinal surgery.
The surface-mounted LEDs 41 can be individually controlled as
described for the embodiment of FIG. 8 to allow any pattern of
central or peripheral retinal illumination to be provided for the
particular application. An embodiment of the present invention
allows a practitioner control over the illumination pattern by
direct control of individual surface-mounted LEDs 41. A controller
17 is connected to each individual LED or a series of LEDs to allow
a practitioner spatial, temporal, and intensity control over the
surface-mounted LEDs 41. A practitioner can choose which LED lights
are on and their radiance. By illumination of only a few LEDs in
the ring of LEDs, this allows for selective sectoral illumination
of the retina. Illumination can be focused on peripheral versus
central retina, allowing a practitioner to focus on one area of the
retina 101. This maintains an advantage over contemporary slit lamp
illumination in that larger areas of the retina can be illuminated
at one time that afforded by the slit beam. The image 100 also has
significantly reduced reflections and enhanced image contrast
compared to contemporary designs. This sectoral illumination
capability is advantageous to practical use of the invention.
Patient tolerance to illumination varies significantly, and control
of individual LED brightness allows an illumination pattern to be
set that is both comfortable for the patient and allows evaluation
and treatment of specific areas of the retina. This particular
embodiment envisions use of a controller 17 with surface-mounted
LEDs 41 to allow for sectoral illumination. However, the particular
embodiment used to control illumination levels and allow sectoral
illumination may comprise other methods, including but not limited
to a diaphragm, LCD mask, or neutral density filter. There is no
capability for this specific control of the illumination pattern in
contemporary designs, which limits their practical use in some
patients.
In an embodiment, the controller 17 can be triggered by a camera
flash to allow all the surface-mounted LEDs 41 to turn on
momentarily at high brightness for the purposes of retinal
photography. In another particular embodiment, the controller 17
can be used to control the intensity of infrared LEDs to allow
focusing of the image from the handheld lens and then control
interspaced white LEDS, turning them on momentarily at high
brightness for the purposes of retinal photography
FIGS. 11 A-11B shows the outer casing of handheld lens 11 in an
exemplary embodiment of the present invention in side ways position
and upward position, respectively. A battery compartment 110 is
located on the side of the handheld lens 11 to house batteries to
power the illumination source, as well as to house the fiber optic
cable 2 and light source 1, as required by some embodiments
described above. The dimensions of the various embodiment of this
invention may be less than, for example, approximately 20% of the
size of commercial embodiments of contemporary designs. With a
battery powering the self-contained illumination of various
embodiments, no external AC power source or external electrical or
fiber optic cords are necessary to connect to the handheld lens.
The focal point of the handheld lens remains at the standard
distance to allow for ophthalmic slit lamp biomicroscopy by a
trained practitioner with this lens. While it may be advantageous
to have the power source and/or light source provided integrally
connected with the hand held lens 11 or completely inside the hand
held lens 11, it should be appreciated that it may be provided from
an exterior source, or any combination thereof.
While an intended use for this lens is directed towards clinical
slit lamp biomicroscopy, the scope of its use and the claims with
the current invention include additional applications. In one
embodiment the lens will be used for application of laser
photocoagulation to the retina in patients requiring this treatment
such as diabetics and those with retinal defects. In an embodiment
the laser aiming beam and laser application could be provided as
conventionally occurs via the slit lamp biomicroscope. However,
rather than using the slit illumination of the slit lamp to
illuminate the retinal details, built in illumination in the
handheld contact lens would serve this function. This has the
potential to allow a 165 degree full illumination of the retina
during laser application, which is not possible with contemporary
designs. It also allows for sectoral retinal illumination with
significantly reduced image aberrations than available with
contemporary designs.
In an embodiment this lens may be adapted for use with existing
retinal cameras or other image recording devices as desired or
required. FIG. 12A illustrates one such embodiment. The handheld
lens 11, designed to provide even illumination of a patient's
retina 101 through providing annular illumination, is attached to a
lens-to-camera interface 121. The lens-to-camera interface 121 is
also attached to an image recording device 122. The lens-to-camera
interface 121 comprises the optics and housing needed to couple the
image produced by the handheld lens to the image recording device
122 to allow the handheld lens image to be recorded. Most
conventional retinal cameras are capable of approximately 60
degrees field of view of the retina, which encompasses only the
most central aspects of the retina. Widefield photography requires
use of a contact lens, but is not possible with a standard retina
camera due to the design of the retina camera illumination. One
particular implementation of the embodiment illustrated in FIG. 12A
is shown in FIG. 12B.
It should be appreciated that an aspect of the various embodiments
of the invention provided throughout this disclosure may include
images or data obtained by handheld lens 11 that may be stored or
communicated with the image recording device 122 as shown, or other
devices not shown. For instance, images (or other data) may be
communicated through a transmission module (not shown) to either a
local and/or remote location(s). It should be appreciated that the
local and/or remote location(s) may include, but are not limited
thereto, a user, a processor, a display, a database, an archive,
PDA, computer, lap top, network, or any combination thereof. This
may enable specialists (or other practitioners or users) to
complete diagnostics using the images (or other data) at local or
remote locations and enable telemedicine practices (e.g., internet
practices, etc.) to be used. In using telemedicine practices (e.g.,
internet practices, etc.), the images or other data may be
transmitted through the transmission module (hardwire, wireless,
etc. as desired or required) to a remote location(s) where they are
later reviewed by ophthalmologists or other trained specialists. If
the image shows that the patient has a disease or defect, the
patient may then be referred to a specialist for more testing and
treatment. In this situation, images of the hand held lens
system/device can be recorded at a primary care clinic without the
need for specialists at the primary care clinic to perform the
diagnosis. Reviewing images by specialists at a remote location may
allow for more efficient processing and diagnostics of the recorded
images or other data. This may allow a greater number of patients
(or subjects) to be screened for retinal diseases, etc. at a lower
overall cost.
In an embodiment it is provided that xenon or LED illumination will
be used built into the handheld lens 11. The retina camera can then
be adapted to disable its illumination and rely on the
self-contained handheld lens illumination to enable widefield
retinal photography.
FIG. 13A shows a view of a model eye using the embodiment of FIG.
10. In the image, only part of the retina 101 is illuminated. The
controller 17 is being used to selectively illuminate only this
portion of the retina 101.
FIG. 13B shows a view of a model eye using the embodiment of FIG.
10. Each of surface-mounted LEDs 41 is illuminated, illuminating
the patient's retina 101.
FIG. 13C shows an image taken by a contemporary retinal camera. The
image is obscured by corneal haze. Comparing FIGS. 13B and 13C
reveals that the handheld lens of FIG. 10 is able to achieve a
similar or higher quality image than contemporary retinal
cameras.
In another embodiment this self-illuminated handheld lens 11 may be
used to adapt existing surgical vitreoretinal contact lenses used
for vitreoretinal surgery. Handheld lens 11 will provide
illumination of the retinal surface to enable better visualization
during vitreoretinal surgery. It would also potentially permit
bimanual vitreoretinal surgery as a separate handheld light fiber
to illuminate the retina as used in conventional vitreoretinal
surgery may no longer be necessary if the surgical vitreoretinal
contact lens provides sufficient illumination. In one particular
embodiment, individual control over the pattern of retinal
illumination would be provided using the controller 17 or other
method, for example, as described for the embodiments of FIG. 7,
FIG. 8, and FIG. 10.
In short, an aspect of the present invention provides a handheld
fundus lens with built in self-illumination to permit widefield
viewing of the retina. Current handheld fundus lenses rely on
external slit lamp biomicroscope illumination of the retina, which
has the disadvantage of significant image aberrations and
reflections as well as a limited slit area of retina that can be
viewed at one time. The novel illumination design of the various
embodiment of the present invention overcomes all of these
limitations to allow more detailed examination of the entire
retinal surface in any pattern needed and permit safer surgical
procedures to be performed on the retina.
Accordingly, the revolutionary medical device (and related method)
of the various embodiments will allow retina specialists their
first clear detailed view of the retina during clinical exam at the
slit lamp in 100 years. Further, it has the potential to completely
change the way ophthalmologists examine the retina, and to
dramatically improve the standard to which we are held on the
detail of our clinical retina exam. It provides the potential to
bring the same technological capabilities that we currently have in
retina photography to our day to day clinical examination of the
eye. In some cases it may eliminate the need for separate
procedures to obtain retina photography as the photographic view at
the ophthalmic slit lamp may be of sufficient. This device (and
related method) can also potentially transform how both laser
surgical procedures and vitreoretinal surgery is practiced. It will
be immediately clear exactly were the laser aiming beam is located
on the surface of the retina in a way which is not currently
possible. During vitreoretinal surgery it may allow use of bimanual
procedures, instead of rendering one hand relegated to holding the
illumination probe. This device will substantially improve patient
care by increasing the quality of the exam, allowing better
diagnosis of retinal disease. It will also render laser and
surgical procedures on the retina much safer by providing a clear
panoramic view of the retina. This is, simply put, one of those few
devices that has the possibility to transform how we practice
ophthalmology.
Commercial potential for this device (and related methods) is
extremely high. There is no competing technology currently in the
marketplace other than non-illuminated handheld fundus lenses with
their associated disadvantages. The commercial potential will be
impacted by price point over these existing lenses. It is therefore
expected that ophthalmology clinics in the United States and
various countries around the world will purchase these lenses if
they are made available.
It should be appreciated that various sizes, dimensions, contours,
rigidity, shapes, flexibility and materials of any of the
embodiments discussed throughout may be varied and utilized as
desired or required.
It should be appreciated that as discussed herein, a subject may be
a human or any animal. It should be appreciated that an animal may
be a variety of any applicable type, including, but not limited
thereto, mammal, veterinarian animal, livestock animal or pet type
animal, etc. As an example, the animal may be a laboratory animal
specifically selected to have certain characteristics similar to
human (e.g. rat, dog, pig, monkey), etc. It should be appreciated
that the subject may be any applicable human patient, for
example.
An aspect of an embodiment of FIG. 10 provides a matrix of LEDs to
allow an exquisite degree of temporal and spatial control of
retinal illumination not available in contemporary designs. An
aspect of this embodiment may be necessary to practice in some
patient populations depending on application or patient
constraints. In particular, placement of the LEDS directly on the
curved surface allows for a smaller LED housing 31 than in other
embodiments, which may be needed for certain patient populations
such as neonates, or for particular applications such a
vitreoretinal surgery.
LEDs can be individually controlled as described for the embodiment
of FIG. 8 to allow any pattern of central or peripheral retinal
illumination to be provided for the particular application. An
embodiment of the present invention allows a practitioner control
over the illumination pattern by direct control of individual LEDs
10. A microcontroller XX is connected to each individual LED or a
series of LEDs to allow a practitioner spatial, temporal, and
intensity control over the LEDs 10. A practitioner can choose which
LED lights are on and their radiance. By illumination of only a few
LEDs in the ring of LEDs, this allows for selective sectoral
illumination of the retina. Illumination can be focused on
peripheral versus central retina, allowing a practitioner to focus
on one area of the retina. This maintains an advantage over
contemporary slit lamp illumination in that larger areas of the
retina can be illuminated at one time that afforded by the slit
beam. The image also has significantly reduced reflections and
enhanced image contrast compared to contemporary designs. This
sectoral illumination capability is essential for reduction of the
embodiment to practice. Patient tolerance to illumination varies
significantly, and control of individual LED brightness allows an
illumination pattern to be set that is both comfortable for the
patient and allows evaluation and treatment of specific areas of
the retina. This particular embodiment envisions use of a
microcontroller with LEDs to allow for sectoral illumination.
However, the particular embodiment used to control illumination
levels and allow sectoral illumination may comprise other methods,
including but not limited to a diaphragm, LCD mask, or neutral
density filter. There is no capability for this specific control of
the illumination pattern in contemporary designs, which limits
their practical use in some patients.
In one particular embodiment, the microcontroller can be triggered
by a camera flash to allow all LEDS to turn on momentarily at high
brightness for the purposes of retinal photography. In another
particular embodiment, the microcontroller can be used to control
the intensity of infrared LEDs to allow focusing of the image from
the handheld lens and then control interspaced white LEDS, turning
them on momentarily at high brightness for the purposes of retinal
photography.
The devices, systems, compositions, computer program products, and
methods of various embodiments of the invention disclosed herein
may utilize aspects disclosed in the following references,
applications, publications and patents and which are hereby
incorporated by reference herein in their entirety: 1. U.S. Pat.
No. 3,944,341, Mar. 16, 1976, to Oleg Pomerantzeff, "Wide-Angle
Ophthalmoscope and Fundus Camera." 2. U.S. Pat. No. 5,822,036, Oct.
13, 1998, to Norbert Massie, "Eye Imaging Unit Having a Circular
Light Guide." 3. U.S. Pat. No. 7,048,379, May 23, 2006, to Joseph
Miller and James Schwiegerling, "Imaging Lens and Illumination
System." 4. International Patent Application Publication No. WO
2004/082465 A2, Miller, et al., "An Imaging Lens and Illumination
System", Sep. 30, 2004.
In summary, while the present invention has been described with
respect to specific embodiments, many modifications, variations,
alterations, substitutions, and equivalents will be apparent to
those skilled in the art. The present invention is not to be
limited in scope by the specific embodiment described herein.
Indeed, various modifications of the present invention, in addition
to those described herein, will be apparent to those of skill in
the art from the foregoing description and accompanying drawings.
Accordingly, the invention is to be considered as limited only by
the spirit and scope of the following claims, including all
modifications and equivalents.
Still other embodiments will become readily apparent to those
skilled in this art from reading the above-recited detailed
description and drawings of certain exemplary embodiments. It
should be understood that numerous variations, modifications, and
additional embodiments are possible, and accordingly, all such
variations, modifications, and embodiments are to be regarded as
being within the spirit and scope of this application. For example,
regardless of the content of any portion (e.g., title, field,
background, summary, abstract, drawing figure, etc.) of this
application, unless clearly specified to the contrary, there is no
requirement for the inclusion in any claim herein or of any
application claiming priority hereto of any particular described or
illustrated activity or element, any particular sequence of such
activities, or any particular interrelationship of such elements.
Moreover, any activity can be repeated, any activity can be
performed by multiple entities, and/or any element can be
duplicated. Further, any activity or element can be excluded, the
sequence of activities can vary, and/or the interrelationship of
elements can vary. Unless clearly specified to the contrary, there
is no requirement for any particular described or illustrated
activity or element, any particular sequence or such activities,
any particular size, speed, material, dimension or frequency, or
any particularly interrelationship of such elements. Accordingly,
the descriptions and drawings are to be regarded as illustrative in
nature, and not as restrictive. Moreover, when any number or range
is described herein, unless clearly stated otherwise, that number
or range is approximate. When any range is described herein, unless
clearly stated otherwise, that range includes all values therein
and all sub ranges therein. Any information in any material (e.g.,
a United States/foreign patent, United States/foreign patent
application, book, article, etc.) that has been incorporated by
reference herein, is only incorporated by reference to the extent
that no conflict exists between such information and the other
statements and drawings set forth herein. In the event of such
conflict, including a conflict that would render invalid any claim
herein or seeking priority hereto, then any such conflicting
information in such incorporated by reference material is
specifically not incorporated by reference herein.
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